The invention relates to the manufacture of a multi-layered (composite) card, or any like instrument or document.
The term “card” or “cards” as used herein, and in the appended claims, is intended to include a large variety of documents and instruments such as transactional (financial) cards, identification (including a National ID or Driver's License) cards, electronic passport pages, gift cards, documents for holding permanent and long lasting records such as medical records or security cards, or other plastic cards used for promotion of a product or organization.
A known scheme for providing a card with an image includes a screen printed image and the use of clear ultra violet (UV) cured screen printing to create a depression of the metallic foil during lamination. A process for making such a card and some of the features of such a card is illustrated with respect to FIG. 5. As shown in FIG. 5, a deformable metal layer 500 may have a pattern (501a, 501b) formed on the back (top surface in FIG. 5) surface of layer 500. Due to the nature of the screen print material, the printed pattern will consist of various domed-like elements (501a, 501b) distributed on the top surface of layer 500 with the dome like elements having a cross section which appears generally like a semicircle. To form an image on the front side of the layer 500, at least one layer 503 of non-conformable material is positioned over (in back of) the printed pattern and a layer 505 of conformable material is placed in front (below in FIG. 5) of the deformable layer 500. A sandwich is thus formed comprising of a non-conformable layer 503, a patterned region 501, a deformable layer 500 and a conformable layer 505. The sandwich is then laminated by the application of lamination plates 510a and 510b above and below the sandwich layers. The lamination plates apply a predetermined temperature and pressure to the sandwich to cause the transfer of the pattern onto the deformable layer 500. A card formed in accordance with the prior art will have the features shown in FIG. 5C. The domed pattern (501a, 501b) is transferred to the deformable layer 500 and the conformable layer 505. There is distortion (spread) of the pattern during the transfer since the print pattern is being forced into the deformable layer and the underlying conformable layer. Nevertheless, the domed pattern (501a, 501b) will cause a corresponding embossment (protuberance) extending along the outer surface of layer 500.
However, as shown in FIG. 5C, only rounded edges can be formed with this process, preventing the formation of a sharp detailed pattern. [This will typically “distort” almost all of the thickness of the screen print (typically around 0.0005 inches).] The resulting pattern using screen printing is not very sharp. This is shown in FIG. 5C which illustrates the reason for the lack of sharpness. Print material may be deposited (raised print) on a foil layer. The print material will typically have a rounded distribution. When a laminating plate is applied to the raised print layer it will push the foil outward (downward in FIG. 5) and create an embossment on the opposite side of the foil layer. However, this embossment does not have sharp edges and a resulting image will not be clear and well defined.
It is an object of the invention to manufacture a card formed with materials having certain “flow” characteristics as a function of temperature to enable a clear, well defined, 3-D image to be produced within the card.
It is another object of the invention to manufacture an embossed card whose top and bottom surfaces are flat and with reduced internal surface imperfections.